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variablespentahokettlepentaho-spoon

Pentaho Data Integration setVariable not working

I am on PDI 7.0 and have a "Modified Java Script Value" step inside a transformation as below:

var numberOfDays = 100;
Alert(numberOfDays);
setVariable("NUMBER_OF_DAYS", numberOfDays, "r");
Alert(getVariable("NUMBER_OF_DAYS", ""));

However, when I run the transformation, the first Alert correctly throws 100, but the next Alert is blank (meaning the variable is not set).

What is wrong here?

Solution

  • As a rule of thumb, you should never set a variable and read it within the same transformation.

    See a warning that pops up in Spoon when setting up Set Variables step:

    enter image description here

    That said, what you could do, if you really insist on setting this via Java Script is the following design:

    enter image description here

    where

    1) Set variable transformation is used to set the value:

    var numberOfDays = 100;
Alert(numberOfDays);
setVariable("NUMBER_OF_DAYS", numberOfDays, "r");

    2) Get variable transformatoin only reads it

    Alert(getVariable("NUMBER_OF_DAYS", ""));

    Both transformations use the same steps, but they have separate task.